A stereoscopic image display provides a sense of depth by individually sending substantially two-dimensional images to the right eye and the left eye of a person, allowing the images to be integrated in the brain, and allowing the integrated image to be stereoscopically viewed. For this purpose, it is necessary to individually form images for generating a parallax in advance and to correct the images when the images are sent to the corresponding eyes, or it is necessary to separate a two-dimensional image into an image to be viewed by the right eye and an image to be viewed by the left eye.
In the method for separating a two-dimensional image, it is not necessary to wear polarized glasses or the like for correcting an image and thus a stereoscopic image can be viewed by the naked eye. Examples of the method for separating a two-dimensional image include a method using a lenticular lens and a parallax barrier method. The lenticular lens is a lens that separates an image into two images by determining the width of a certain image that can be viewed by one eye using refraction by the lens. As the lenticular lens, a birefringent lens having a shape in which semicylinders are arranged in a line is used for generating a parallax.
Regarding a characteristic required for the lenticular lens, a small change in the refractive index with respect to the temperature change is required in order to use the lenticular lens in a wide range of environments. To meet this requirement, a technique has been proposed in which a cured liquid crystal polymer is used as a material of a birefringent lens (refer to PTL 1 and NPL 1).
However, many different types of liquid crystal polymers exist, and in the case where a cured liquid crystal polymer is simply used as a material of a birefringent lens without studying the material in detail (refer to PTL 1), problems in terms of optical characteristics, durability, productivity, etc. of the lens may occur. A technique in which a bifunctional liquid crystalline monomer is used as a birefringent lens material is disclosed (NPL 1). However, this material has problems in terms of optical characteristics and productivity, and thus the application of this material as a birefringent lens material composed of a liquid crystal polymer has not proceeded.